package lab02.test01;

import java.util.Scanner;

public class Main {


    static int count = 0;
    static int n = 0;

    static void step(int k, int step) {

        if (k > n)
            return;

        if (k == n && step % 2 == 0) {

            count++;
            return;
        }

        step(k + 1, step + 1);
        step(k + 2, step + 1);
    }

    public static void main(String[] args) {


        Scanner scanner = new Scanner(System.in);
        n = scanner.nextInt();

        step(0, 0);
        System.out.println(count);
    }
}
